1. Field of the Invention
The present invention relates to an apparatus and a method for capturing and analyzing video images and, in particular, video images of sediment grains on a river or seabed, in order to determine grain size.
2. Background of the Invention
Researchers such as sedimentologists, marine geologists, and other scientists are interested in studying the surficial sedimentologic geology in lake, river, and ocean environments. Typically, such a study requires manually collecting samples from the bottom (i.e., bed) of the lake, river, and ocean. Once the sediment has been collected, the collected sediment is analyzed for various characteristics including sediment grain size.
A disadvantage with current techniques used to study surficial sedimentologic geology is that actual sediment samples must be taken from the bottom of the body of water. Typically, the manual collection of sediment tends to be time consuming, costly and dangerous.
In accordance with the present invention, an apparatus and a method are provided for capturing and analyzing video images of river, lake or seabed sediment. Close-up images are taken of the sediment without collecting the sediment from the bottom of the body of water. Subsequently, the captured images are analyzed to determine grain size using a suitable image processing algorithm.
According to one aspect of the present invention, an apparatus is provided for capturing and analyzing video images of river, lake, or sea bed sediment containing grains of various sizes from the bottom of a body of water. The apparatus comprises a video imager, including a flat field close-up focus lens, for collecting images of bed sediment containing different grain sizes. A waterproof housing containing said video imager. A weight member is associated with the housing for ensuring that, in operation, the housing can be lowered down to the bed sediment. A video recorder is provided to record the images collected.
In accordance with another aspect of the present invention, a method is provided for analyzing surficial sediment of the bed of a body of water comprising deploying an imaging device at the bed of the body of water and capturing images of the bed. Next, grain size of the sediment is determined by analyzing individual frames of the images captured.
One feature of the present invention is the ability thereof to determine grain size of the sediment without manually collecting sediment from the bottom of a body of water.
An additional feature of the present invention relates to analyzing images captured from the bottom of a body of water to determine grain size.
Yet another feature of the present invention concerns the provision of a video imaging device specifically adapted to withstand the movement and flow of water current present in a highly dynamic, swiftly moving, river environment, thereby allowing the video imaging device to capture images from the bed.
Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows.